GRAPHING EQUATIONS OF LINESHow to graph equations in y = mx + b

WARM UP

1. Write the equation of the line:

2. Write the equation of a line with a slope of – 2 and passing through thepoint (0, -3)

3. Write the equation of a line

passing through the points

(- 2, 4) and (3, - 1)

4. Write the equation of the line

with a slope of 6 and y-intercept

of – 4?

How did we find the equation of a line?

What is the equation of this line?

Today you will learn how to graph a line in the form of y = mx + b.

What do you think this means?

How do you think we are going to do this?

Look at the graph for some ideas.

What does your partner think you should do?

Step one: What is the y-intercept? How would you write this as an ordered pair?

Step two: What is the slope of the line?

Step three: From the y-intercept, move up and over and then down and over in the opposite direction. Plot these points.

Step four: Draw a line through the three points. You must have at least three points.

https://www.youtube.com/watch?v=vIw23jBE-f4

Graph the line y = 2x – 1

1. Identify the y-intercept. (0, -1)

2. Identify the slope. (m = 2)

3. From the y-intercept, rise and run. (rise up two, run over one.) Plot the point.

4. Go back to the y-intercept, rise and run in the opposite direction. Plot the point.

5. Join the dots to form a line.

Graph the line y = -3x + 4

1. Identify the y-intercept. (0, 4)

2. Identify the slope. (m = -3)

3. From the y-intercept, rise and run. (rise up two, run over one.) Plot the point.

4. Go back to the y-intercept, rise and run in the opposite direction. Plot the point.

5. Join the dots to form a line.

Graph the line y = x – 4

1. Identify the y-intercept. (0, - 4)

2. Identify the slope. (m = )

3. From the y-intercept, rise and run. (rise up two, run over one.) Plot the point.

4. Go back to the y-intercept, rise and run in the opposite direction. Plot the point.

5. Join the dots to form a line.

Try this one with your partner:

y = 5x - 3

Are you ready to try one on your own?Try this one:

y = - x + 2

Special lines:

How would you graph the liney = 2?

What do we know about this line?

How do we graph the line x = - 6?

What do we know about this line?

Work to complete the worksheet on graphing lines.

Look back at your notes for help.

Work with a partner if you need to.

Complete the graphing worksheet. If you need additional help, watch the video using the link below.

http://www.showme.com/sh/?h=v7m62S0